adding some more generic boilerplate code

app/src/main/AndroidManifest.xml

@@ -8,17 +8,23 @@
         tools:node="remove" />
 
     <application
+        android:name=".App"
         android:allowBackup="true"
         android:icon="@mipmap/ic_launcher"
-        android:label="@string/app_name"
+        android:label="@string/app_launcher_name"
+        android:roundIcon="@mipmap/ic_launcher"
         android:theme="@style/AppTheme">
-        <activity android:name=".activities.MainActivity">
+
+        <activity
+            android:name=".activities.SplashActivity"
+            android:theme="@style/SplashTheme">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
-    </application>
 
+        <activity android:name=".activities.MainActivity" />
+    </application>
 </manifest>

app/src/main/kotlin/com/simplemobiletools/smsmessenger/App.kt

@@ -0,0 +1,11 @@
+package com.simplemobiletools.smsmessenger
+
+import android.app.Application
+import com.simplemobiletools.commons.extensions.checkUseEnglish
+
+class App : Application() {
+    override fun onCreate() {
+        super.onCreate()
+        checkUseEnglish()
+    }
+}

app/src/main/kotlin/com/simplemobiletools/smsmessenger/activities/MainActivity.kt

@@ -1,13 +1,20 @@
 package com.simplemobiletools.smsmessenger.activities
 
 import android.os.Bundle
-import androidx.appcompat.app.AppCompatActivity
+import com.simplemobiletools.commons.extensions.appLaunched
+import com.simplemobiletools.commons.extensions.checkAppSideloading
+import com.simplemobiletools.smsmessenger.BuildConfig
 import com.simplemobiletools.smsmessenger.R
 
-class MainActivity : AppCompatActivity() {
+class MainActivity : SimpleActivity() {
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_main)
+        appLaunched(BuildConfig.APPLICATION_ID)
+
+        if (checkAppSideloading()) {
+            return
+        }
     }
 }

app/src/main/kotlin/com/simplemobiletools/smsmessenger/activities/SimpleActivity.kt

@@ -0,0 +1,12 @@
+package com.simplemobiletools.smsmessenger.activities
+
+import com.simplemobiletools.commons.activities.BaseSimpleActivity
+import com.simplemobiletools.smsmessenger.R
+
+open class SimpleActivity : BaseSimpleActivity() {
+    override fun getAppIconIDs() = arrayListOf(
+        R.mipmap.ic_launcher
+    )
+
+    override fun getAppLauncherName() = getString(R.string.app_launcher_name)
+}

app/src/main/kotlin/com/simplemobiletools/smsmessenger/activities/SplashActivity.kt

@@ -0,0 +1,11 @@
+package com.simplemobiletools.smsmessenger.activities
+
+import android.content.Intent
+import com.simplemobiletools.commons.activities.BaseSplashActivity
+
+class SplashActivity : BaseSplashActivity() {
+    override fun initActivity() {
+        startActivity(Intent(this, MainActivity::class.java))
+        finish()
+    }
+}

app/src/main/res/layout/activity_main.xml

@@ -3,9 +3,4 @@
     android:layout_width="match_parent"
     android:layout_height="match_parent">
 
-    <TextView
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:text="Hello World!" />
-
 </RelativeLayout>

app/src/main/res/values/colors.xml

@@ -1,6 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
-    <color name="colorPrimary">#6200EE</color>
+
-    <color name="colorPrimaryDark">#3700B3</color>
-    <color name="colorAccent">#03DAC5</color>
 </resources>

app/src/main/res/values/strings.xml

@@ -1,3 +1,4 @@
 <resources>
     <string name="app_name">Simple SMS Messenger</string>
+    <string name="app_launcher_name">SMS Messenger</string>
 </resources>

app/src/main/res/values/styles.xml

@@ -1,11 +1,5 @@
 <resources>
 
-    <!-- Base application theme. -->
+    <style name="AppTheme" parent="AppTheme.Base" />
-    <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
-        <!-- Customize your theme here. -->
-        <item name="colorPrimary">@color/colorPrimary</item>
-        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
-        <item name="colorAccent">@color/colorAccent</item>
-    </style>
 
 </resources>